What Is Lobular Carcinoma In Situ

Overview

Lobular carcinoma in Situ (LCIS) is a condition in which abnormal cells are found in the lobules of the breast. Although LCIS sounds like a type of cancer, it isn’t; it is considered to be a marker of increased breast cancer risk.¹ Women with LCIS have a roughly 9-10-fold higher risk of developing invasive breast cancer at some point in their lifetime compared to women without LCIS.¹

What does lobular carcinoma in situ mean?

To understand the condition, it might help to break down what the term “Lobular carcinoma in Situ” means.

• Lobules: Glands within the breast that produce milk
• Carcinoma: A type of cancer that affects epithelial tissue
• In Situ: Latin term that can mean locally. Medically, it's used to mean that growth hasn’t spread from where it originated and so is not cancerous. Growths that are in situ can become cancerous in time, however, spreading elsewhere in the body. 

Together, “Lobular carcinoma in Situ” describes a non-cancerous growth within the milk producing glands of the breast.

Causes

LCIS was first described by Foote and Stewart in 1941 as a distinct form of breast cancer that originates in the breast lobules.² The exact cause of LCIS is not known, but certain factors have been identified that may increase a person's risk of developing the condition. These risk factors include:³

• Family history: Women with a family history of breast cancer are at increased risk of LCIS.
• Age: The risk of LCIS increases with age, and the condition is most commonly diagnosed in women in their 50s and 60s.
• Genetic mutations: Loss of function mutations in CDH1, a gene that encodes for E-cadherin, a protein involved in cell-cell adhesion, has been identified in a significant number of patients with LCIS and invasive lobular carcinoma (ILC).⁴

Having one or more of these risk factors does not guarantee that a person will develop LCIS, and many women with LCIS do not have any known risk factors. Nevertheless, it is important to be aware of these risk factors and to work with a healthcare provider to assess your risk of LCIS and develop a plan for monitoring and managing your breast health.

Signs and symptoms

It is important to be aware of any changes in the breast, including:⁵

• A change of the breast in size or shape
• A lump or thickening inside the breast
• Dimpling of the skin of the breast
• Change of colour, warmth, or swelling of the breast
• Nipple discharge or inverted nipple

It is crucial to report any changes in the breast to your healthcare provider promptly, as these may be signs of a more serious condition, such as breast cancer.

Diagnosis

LCIS is diagnosed by a combination of biopsies and scans.

Biopsy

LCIS may be detected incidentally during a biopsy performed for another reason, such as a lump in the breast or an abnormal mammogram. If LCIS is suspected, additional tests may be performed to confirm the diagnosis, including:^5,6

• Fine-needle aspiration (FNA) biopsy: This procedure involves using a thin needle to remove a small sample of tissue from the affected area for examination under a microscope.
• Core biopsy: This procedure involves using a larger needle to remove a larger sample of tissue from the affected area for examination under a microscope.
• Surgical biopsy: In some cases, a surgical biopsy may be performed to remove a larger sample of tissue from the affected area for examination under a microscope.

Scans

Breast imaging techniques, include:⁶

• Mammogram 
• Ultrasound

However, these techniques may not always be able to distinguish LCIS from other benign breast conditions. To differentiate a biopsy may be necessary to confirm the diagnosis. 

Dual-energy computed tomography (DECT) scans may also be done to diagnose LCIS. It is important to note that dual-energy CT is not currently a routine screening tool for breast cancer, and its use in the detection of LCIS is still being studied.⁷

Management and treatment

The management and treatment of LCIS depends on a woman's age, overall health, and personal preferences, as well as the size, location, and extent of the LCIS. 

Some common options for managing and treating LCIS include:

• Close monitoring: Regular mammograms and other imaging tests, as well as clinical breast exams, to ensure that the LCIS does not progress to invasive breast cancer.
• Hormonal therapy: Women who are postmenopausal or have a high risk of developing breast cancer may be prescribed hormonal therapy to reduce the risk of developing invasive breast cancer.
• Surgery: In some cases, women with LCIS may opt for surgery, such as a prophylactic mastectomy or a breast-conserving surgery, to remove the affected breast tissue and reduce the risk of developing invasive breast cancer.
• Radiation therapy: Radiation therapy may be used in conjunction with other treatments, such as surgery or hormonal therapy, to reduce the risk of breast cancer.

It is important to work with a healthcare provider to determine the best course of treatment for LCIS, as the optimal management and treatment plan will vary depending on a woman's individual circumstances.

FAQs

How can I prevent lobular carcinoma in situ?

There is no guaranteed way to prevent lobular carcinoma in situ (LCIS), but there are several steps that women can take to reduce their risk of developing the condition, including:

• Maintaining a healthy weight: Being overweight or obese has been linked to an increased risk of LCIS and other types of breast cancer.
• Engaging in regular physical activity: Regular physical activity has been shown to reduce the risk of LCIS and other types of breast cancer.
• Avoiding alcohol: Excessive alcohol consumption has been linked to an increased risk of LCIS and other types of breast cancer.
• Quitting smoking: Smoking has been linked to an increased risk of LCIS and other types of breast cancer.
• Having regular breast cancer screenings: Regular breast cancer screenings, such as mammograms and clinical breast exams, can help detect LCIS and other types of breast cancer in their early stages when they are most treatable.
• Talking to your healthcare provider about your family history: Women with a family history of breast cancer may be at an increased risk of LCIS and other types of breast cancer. 

Women with LCIS should work closely with their healthcare provider to develop a plan for monitoring and managing their risk.

Who are at risk of lobular carcinoma in situ?

Women who are at increased risk of LCIS and breast cancer include:

• Women with a family history of breast cancer: Women with a close relative (such as a mother, sister, or daughter) who has been diagnosed with breast cancer are at increased risk of LCIS and other types of breast cancer.
• Women who have been exposed to estrogen for a prolonged period of time: Women who have taken hormone replacement therapy (HRT) or who have had their ovaries removed before menopause are at increased risk of LCIS and other types of breast cancer.
• Women who are overweight or obese, especially after menopause, are at increased risk of LCIS and other types of breast cancer.
• Women who regularly consume alcohol are at increased risk of LCIS and other types of breast cancer.
• Women with a personal history of LCIS or ductal carcinoma in situ (DCIS) are at increased risk of developing breast cancer in the other breast.

It is important to note that LCIS is a relatively rare condition, and the majority of women with LCIS will not develop invasive breast cancer.

How common is lobular carcinoma in situ?

Lobular carcinoma in situ (LCIS) is a relatively uncommon condition, affecting less than 1% of all women. However, it increases a woman's risk of developing invasive breast cancer in the future. Despite its relative rarity, it is important for women who have been diagnosed with LCIS to take steps to monitor their risk and take preventive measures, as recommended by their healthcare provider.

When should I see a doctor?

You should see a doctor if you experience any symptoms or changes in your breasts that are concerning to you, such as:

• Lumps or thickening in the breast tissue
• Changes in the shape or size of your breast
• Discharge from the nipple
• Inverted nipples
• Pain or tenderness in the breast
• Dimpling or puckering of the skin on the breast
• Redness, warmth, or swelling of the breast

If you have any concerns about your breast health, it is best to see a doctor for a thorough evaluation. Early detection and prompt treatment of breast cancer and LCIS can improve outcomes and reduce the risk of complications.

Summary

Lobular carcinoma in situ, also known as LCIS, is a non-cancerous breast condition that is considered a risk factor for developing invasive breast cancer. Proper diagnosis and follow-up of LCIS can help ensure that women receive appropriate care and treatment to reduce their risk of developing invasive breast cancer.

It is also important for women to be informed about the risks associated with LCIS and to discuss their options for monitoring and management with their healthcare provider. This can include regular breast cancer screening, as well as lifestyle changes and risk reduction strategies to help lower the risk of developing invasive breast cancer.